1. Field of the Invention
The present invention relates to devices for custom fitting foot gear. In particular, the present invention relates to devices for enlarging specific areas within a shoe or boot, such as a ski boot. Applicant claims the benefit of the filing date of his provisional application, Ser. No. 60/014,800, filed Apr. 4, 1996.
2. Discussion of Background
A ski boot should transfer the movements of a skier's foot directly to the ski. A typical ski boot comprises a hard plastic outer shell with an inner boot made from a flexible material. A ski boot should fit a skier's foot comfortably, but snugly to transfer movement of the foot to the boot, and then to the ski to which the boot is rigidly attached. Unfortunately, with the infinite number of shapes that feet come in, providing a set of standard sizes of ski boots that fit feet perfectly is not possible. While it may be possible to make a mold and form an inner flexible boot to perfectly fit a skier's foot, this method does not always work the best. For instance, the inner boot is able to flex and change shape depending on the type and direction of forces that the skier's foot exerts on the inner boot. Consequently, the inner boot, after extended use, will no longer fit the skier's foot as snugly as it did when new. Additionally, it is not practical to make a mold for every skier's foot as the cost per skier would be prohibitive for most skiers.
There have been attempts in the prior art to devise methods and implements to customize ski boots. For example, see U.S. Pat. No. 5,337,432 which issued Aug. 16, 1994 to Pirhonen and U.S. Pat. No. 4,060,863 which issued Dec. 6, 1977 to Brown. Each of these references shows a device that works in conjunction with a heating element to locally heat the outside portion of the outer shell of the ski boot. The implements described in these patents exert a force against the boot from its interior and against one side of the boot, while the exterior is being heated. The application of force against a heated boot results in the boot being locally expanded. Moreover, in each of the above references, a hydraulic unit is used to supply this force solely to the medial side of the boot. However, there is a need in many instances to stretch the lateral side of the boot, or possibly the toe or heel areas. Additionally, it may be necessary to stretch the lower leg portion of the ski boot, for which the above devices are unsuitable. Furthermore, the use of hydraulic equipment within the boot can result in hydraulic fluid leaks within the interior of the boot. Consequently, there is a need for a device that is simple to use and easy to manufacture for locally enlarging or stretching a variety of areas within a ski boot.